Effects of Hyperglycemia on Vascular Smooth Muscle Ca²⁺ Signaling

Figure 7

Effect of glucose on sarcoplasmic reticulum ATPase (SERCA) activity in A7r5 VSM cells. A7r5 cells, cultured under HG, NG, and OC, were loaded with Fura2-AM and cytosolic Ca²⁺ was monitored following treatment with 20 μM PE and 1 mM lanthanum chloride (La³⁺) at the time points indicated by the respective arrows (a). Time to half decay after the La³⁺ treatment was then measured and compared between the different conditions (b). Protein and gene expression of SERCA from A7r5 cells cultured under the different condition were determined by western blot and real-time PCR, respectively (c–e). Effect of NAC on HG-induced SERCA compromised activity was determined in A7r5 cells cultured in the presence of NAC for 2 weeks prior to the determination of SERCA activity (f). The effect of HG on ROS generation in cells shifted for 30 min from NG and OC to HG and from HG to NG (g) was measured by the DCFH assay. Data are presented as from at least three independent experiments done each in triplicate. .

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